This invention belongs to the field of agricultural chemistry, and provides to the art a new method of protecting plants from soil-borne phytopathogens. Such phytopathogens, which cause plant diseases commonly known as wilts and rots, have long been recognized as enemies of crop production. The phytopathogens are to be found in most agricultural soils, and attack germinating seeds and seedlings. Since the damage is done in the soil-buried parts of the plant, it has been particularly difficult to protect plants from such phytopathogens.
A few prior publications are important to the background of this invention. U.S. Pat. Nos. 3,764,681 and 3,839,569, of the present inventor, disclosed the fungicidal efficacy of tetrazolo[1,5-a]quinolines and s-triazolo[4,3-a]quinolines, respectively. Belgian Pat. No. 803,098 and West German Offenlegungsschrift No. 2,249,350 disclosed that certain imidazoquinoxalines were also useful as agricultural fungicides.